Sliding clasp fasteners



Oct. 14,1958 v z. DEsHAw 1 4 2,855,551

' SLIDINGCLASP FASTE'NERS I Filed Nov. 25, 1953 2 Smets-sheet 1 Filed Nov. 25, 1953 z. DEsHAw 2,855,651

SLIDING CLASP FASTENERS 2 Sheets-Sheet 2 n venlor um jim/7W By WZ A ttorn e y United States Patent-"O SLIDING CLASP FASTENERS Zoltan Deshaw, London, England Application November 25, 1953, Serial No. 394,404

Claims priority, application Great Britain December 1, 1952 The present invention relates to slidersfor sliding clasp fasteners of the kind comprising opposed `shields for guiding two fastener stringers through the slider, the said shields being joined so as to allow spreading apart of the shields at any position of the slider on the stringers at which the slider may have jammed whereby to overcome the jamming. i

It is an object of the invention to provide animproved and simplified slider of the kind described.

It is another object of the invention to provide a slider of the kind described wherein means are provided for preventing unintentional spreading of the slider shields.

It is a further object of the invention to provide a slider of the kind described wherein simple cam means are provided for preventing unintentional spreading of the slider shields.

AIt is still another object of the invention to provide a slider of the kind described, which comprises only three components which allow the slider to be easily assembled.

These and other objects and advantages of the invention will become apparent to those skilled in Vthe art from the following detailed description when read in conjunction with the accompanying drawings, which by way of example only illustrate a specific embodiment of the invention and in which: I

Fig. 1 illustrates a perspective view of a slider of the invention in position on two stringers of a sliding clasp fastener;

Fig. 2 similarly illustrates the slider With the slider shields spread apart, the slider being detached from the fastener stringers;

Fig. 3 shows an exploded perspective View of the slider;

Fig. -4 shows a side view of the slider;

Fig. 5 shows a similar side view of the slider with the slider shields spread apart;

Fig. 6 shows a plan view of the slider; and,

Fig. 7 shows a plan view of -one of the slider shields.

The slider illustrated in the drawings Vcomprises two opposed slider shields -1`and 12, and an operating tab 22. For convenience, the shields 1 and 12 will hereinafter be termed the lower and the upper shield respectively.

The lower shield 1 comprises a base 2, side walls 3, and a wedge-shaped projection 4. The projection 4 forms part of a riser element generally denoted by reference numeral 5 and provided with two transverse bearing grooves 6 and 7 (see Fig. 3.), with a rib 7a providing a wedge 8 an'd'with faces 9 parallel with the base 2, the faces 9 extending from the bearing groove 6 towards the lgroove 7 4vand terminating in a vertical wall 10 (see also Figs. `4, 5 "and 46) approximately underneath the lbearing groove 6.

The upper shield 12 comprises a base 13 and side walls 14 adapted to overlie the side walls 3 of the lower shield 1. The base 2 of the lower shield 1, its side walls 3, the base 13 of the upper shield 12, its side walls 14 and the wedge-shapedA projection 4 are arranged to form, in known manner, diverging channels for the passage of interlocking members of two stringers 41 in connec- 2,855,651 Patented Oct. 14, 1958 ICC tion with which the slider is used. The base 13 of the vupper shield 12 has a wide perforation 16 merging at `shoulders 19 into a narrow slot 15 open at 115 at the end of the upper shield overlying the wedge 8. Thereby the upper shield 12 is forked, the limbs 17 of the fork being capable of being elastically forced apart from each-other in the general plane of the upper shield 12. The slot 15 narrows still Afurther at so as to provide two Aopposed lateral projections 18. Between the opposed walls of the slot 15 are integral aligned hinge pins 20 which meet, or nearly meet, each other.

The tab 22 for operating the slider is a forking the portions 23 of which are bridged by a pivot pin 24, which may be formed in one piece with 'the forking. The operating tab 22 as a whole may be formed by casting, moulding or stamping. The portions 23 are formed with peripheral cam faces 25 substantially concentric with the axis of the pivot pin 24 and extending through approximately and terminating in a radial or nearly radial shoulder 26 forming a recess 27 with the surface 28 of the operating tab 22. The operating tab :has a locking finger 29 arranged for extending through the perforation 16 in the upper shield 1'2 and engaging `be tween adjacent interlocking members 40 for locking the slider in a desired position on the stringers 41.

In assembling the slider, the hinge pins 20 of the upper shield 12 are located in the bearing groove 6, the upper shield 12 resting with the limbs 17 in surface engagement with the faces 9, and with the lateral projections 18 in contact with the wedge 8. One of each side wall of the bearing groove 6 is peened or turned over to retain the hinge pins 20 in the said bearing groove and to complete the bearing for the said hinge pins. The pivot pin 24 of the operating tab 22 is then located in the bearing groove 7 and one or each side wall of the bearing groove 7 is also peened or turned over to retain the pivot pin 24 inthe said bearing groove and to complete the bearing.

Figs. l and 4 show the slider closed for normal use with the operating tab 22 in the position shown in Fig. l or shown in full lines in Fig. 4; the concentric faces 25 are in contact with, or in close proximity to, the adjacent part of the outer face of the upper shield v12, the said part acting as a stop face so that the shields 1 and 12 cannot hinge open about the hinge pins 20. This stop action persists while for opening or closing the sliding clasp fastener the operating tab 22 is being turned through almost the Whole of its 180 movement until it reaches the position indicated in broken lines at 221 in Figs. 4 and 5 when the shoulders 26 terminating the concentric faces 25 pass beyond the shoulders 19 of the perforation 16 in the base 13 of the upper shield 12 and overlie the perforation 16. When now opposed finger pressure is applied in clothes-peg-operating fashion on the operating tab 22 and on the outer wall of the base 2 of the lower shield 1., as indicated by the arrows A, A in Figs. 4 and 5, the operating tab 22 rocks the upper shield 12 about the hinge pins 20 until the outer surface of the upper shield 12 fully contacts the adjacent face of the operating tab 22 (see Figs. 2 and 5), the portions of the upper shield 12 adjacent the shoulders 19 being accommodated in the recesses 27 of the operating tab 22. Thereby, the slider has been hinged open -for removal from the stringers 41 (Fig. 2). During the rocking movement of ythe 'upper shield 12, the lateral lprojections 18 on the limbs 17 of 4the said shield slide rst along the wedge 8 and subsequently along the straight upright side walls of the rib 7a, and cause the limbs 17 to be elastically forced apart. Thereby it may be achieved that when the operating tab 22 is in the position 221 of Figs. 4 and 5, the rocking movement takes place with a snap action when the nger pressure exerted overcomes the elastic force of the limbs 17. When the slider has been applied again to the stringers 41 it can be closed in clothes-pegoperating fashion by pressing together the spread apart ends of the shields 1 and 12, as indicated by the arrows D, D in Fig; 5. During the closing movement, the projections 18 rst move along the straight upright sidewalls of the rib 7a and subsequently along the wedge 8. As soon as the projections 18 have left the said side walls, the closing of the slider is completed with a snap action due to the elasticity of the limbs 17 forcing the upper shield 12 into its position for normal use.

After continued use and owing to elastic after effects, it may happen that the elasticity of the limbs 17 is reduced, whereby the snap action effect referred to above may be reduced accordingly. However, even in this case, the slider cannot unintentionally become detached from the stringers 41 since during normal use of the slider the concentric cam faces 25 of the operating tab 22 in co-operation with the outer face of the upper shield 12 prevent unintentional spreading apart of the slider shields.

It should be clearly understood that the embodiment described and illustrated is given by way of example only. Many modifications, omissions and additions are possible Without departing from the spirit and scope of the invention as defined in the following claims.

I claim:

1. In and for a sliding clasp fastener, a slider comprising 4opposed shields for guiding two fastener stringers of the sliding clasp fas,Y ner through the slider, the said shields being joined together so as to allow spreading apart of the shields, an operating tab pivoted to the slider so as to be pivotable through approximately 180 about a .pivot axis substantially parallel to the shields when not spread apart and a cam on the said operating tab, the said cam having a raised cani face substantially co-axial with the said pivot axis, the said cam face extending through an angle of approximately 180 but short of the angle through which the operating tab is pivotable, the shield adjacent the operating tab having a perforation, the said operating tab and its cam face being arranged for the cam face to overlie the outer surface of said adjacent shield adjacent its perforation in all pivotal positions of the operating tab which it assumes in normal use for opening and closing the sliding clasp fastener to prevent spreading apart of the shields by the said cam face abuttlng against the said outer surface, the said cam face overlying the said perforation when the operating tab is near one end of its pivotal movement so as to allow the said cam face to enter the perforation when the shields are spread part.

2. In and for a sliding clasp fastener, a slider comprislng opposed shields for guiding two fastener stringers of the sliding clasp fastener through the slider, the said shields being hinged together so as to allow spreading apart `of the shields, an operating tab pivoted to the slider, a cam arranged on the said operating tab for co-operation with the outer surface of the adjacent shield in all positions of the operating tab which it assumes in normal use for opening and closing the sliding clasp fastener, the operating tab and the cam being arranged for the cam to be out of such co-operation when the operating tab is at one end of its pivotal movement, the said adjacent shield having a slot extending in the longitudinal direction of said adjacent shield and being open at one end thereof whereby the said shield is forked so that the limbs of the forked portion of the said shield can be forced apart elastically in the general plane of the said shield, a Wedge, and a riser element both on the other shield and extending therefrom towards the said adjacent shield, the riser element having at least one surface substantially parallel to the said other shield and arranged for the said adjacent shield to rest on the said surface when the shields are closed, the said riser element also having two surfaces substantially perpendicular to the said other shield and merging into two inclined surfaces forming the said wedge, the said forked portion straddling the said wedge, the limbs of the said forked portion being forced apart by the wedge on spreading the shields apart to slide along the said inclined surfaces and subsequently along the said substantially perpendicular surfaces, the movements of the said limbs being reversed on closing the slider shields, whereby the spreading apart and closing of the slider shields is effected under a snap action.

3. In and for a sliding clasp fastener, a slider comprising opposed shields for guiding two fastener stringers of the sliding clasp fastener through the slider, the said shields being hinged together so as to allow spreading apart of the shields, an operating tab pivoted to the slider, so as to be pivotable through approximately 180 about a pivot axis substantially parallel to the shields when not spread apart, a cam on the said operating tab, the said cam having a raised cam face substantially parallel to the said pivot axis, the said cam face extending through an angle of approximately 180 but short of the angle through which the operating tab is pivotable, the shield adjacent the operating tab having a perforation, the said operating tab and its cam face being arranged for the cam face to overlie the outer surface of said adjacent shield adjacent its perforation in all pivotal positions of the operating tab which it assumes in normal use for opening and closing the sliding clasp fastener to prevent spreading apart of the shields by the said cam face abutting against the said outer surface, the said cam face overlying the said perforation when the operating tab is near one end of its pivotal movement so as to v allow the said cam face to enter the perforation when the shields are spread apart, the said perforation merging into a slot extending in the longitudinal direction of said adjacent shield and being open at one end thereof whereby the said shield is forked so that the limbs of the forked portion ofthe said shield can be forced apart elastically in the general plane of the said shield, a wedge, and a riser element both on the other shield and extending therefrom towards the said adjacent shield, the riser element having at least one surface substantially parallel to the said other shield and arranged for the said adjacent shield to rest on the said surface when the shields are closed, the said riser element also having two surfaces substantially perpendicular to the said other shield and merging into two inclined surfaces forming the said wedge, said forked portion straddling the said wedge, the limbs of the said forked portion being forced apart by the wedge on spreading the shields apart to slide along the said inclined surfaces and subsequently along the said substantially perpendicular surfaces, the movement of the said limbs being reversed on closing the slider shields, whereby the spreading apart and closing of the slider shields is effected under a snap action.

References Cited in the le of this patent UNITED STATES PATENTS 2,042,325 Prentice May 26, 1936 2,366,797 Legat lan. 9, 1945 2,495,176 Nissen Ian. 17, 1950 2,526,653 Gerstman Oct. 24, 1950 2,681,490 Okolowicz June 22, 1954 

